Deploying a small cell base station (BS) such as a Microcell BS, a Picocell BS, a Femtocell BS, and so forth in a hotspot zone has drawn a lot of interests for the next generation of wireless communication systems and standards such as the Long Term Evolution advanced standard (LTE-advanced or LTE-A). A user equipment (UE) served by a small cell BS is expected to operate with a lower path loss than a UE served by a Macrocell BS and therefore would enjoy a better channel gain. Additionally, since a small cell has smaller cell coverage relative to a typical base station such as a Macrocell BS, a low mobility UE might operate better under a small cell while a high mobility UE might be more refrained from operating under a small cell because of the possibility of frequent handovers and cell-reselections. As a result, the UEs which may benefit the most in small cell deployments are UEs having low device mobility.
One of the problems of UEs served by small cell base stations could be related to interferences among small cell base stations. Without adequate power controls and meticulous resource planning among small base stations, mutual interferences might occur among the small cell base stations. Another one of the problems could be related to excessive signaling overheads which are exchanged between a BS and a UE.
To expound on the point of signaling overheads, refer to FIG. 1 that illustrates a signaling involved in a resource allocation process in order for data to be exchanged between a BS and UE. Typically the downlink control information (DCI) would be used to carry information including the resource allocations, transmission setting (e.g. MIMO layer number, MIMO precoding matrix) and the modulation and coding scheme intended for one or more UE devices. The DCI info information would be encoded in a control channel such as the physical downlink control channel (PDCCH) under various formats which would carry different information such as uplink resource or downlink resource, power control, and so forth.
Considering the case of a downlink transmission from an eNB 101 to a UE 102, the downlink would include at least one subframez 111 to be delivered from the eNB 101 from the UE 102. A subframe such as the subframe 111 would typically include a control channel such as a PDCCH 121 and a data channel such as a downlink control shared channel (PDSCH) 122. Upon the reception of the subframe 111, the UE 121 would blindly decode the PDCCH 122 to obtain control information including the DCI in order to locate payloads intended for the UE 102. Upon a successful descramble of the DCI using a Radio Network Temporary Identifier (RNTI) that belongs to the UE, the UE would be able to locate specific resource blocks in the PDSCH 122 containing payloads for the UE.
However, currently in a communication standard such as the LTE-advanced standard, the DCI message in a PDCCH 121 would only provide scheduling information for the PDSCH 122 in the same subframe 111. There is currently no established mechanism to schedule multiple subframes per DCI message. Since a UE served by a small cell base station would typically experience a relatively stable channel condition in comparison to a UE served by a Macrocell BS, using a DCI message to allocate resources for each individual subframe might be unnecessary in such circumstance and thus might cause signaling overheads to be wasted.
Specific details related to a UE receiving a PDSCH could be located in a reference such as “Physical Layer Procedures”, 3GPP TS 36.213, V11.2.0, 2013-03.
Therefore, in view of the aforementioned interference problem and the inefficient use of signaling overheads under small cell operations, there could be a need for a base station and a UE which operate with a multi-subframe scheduling mechanism.